Traditionally, high abundance of Total Organic Carbon (TOC)—comprising kerogen, bitumen, and mobile hydrocarbons—is considered good for reservoir quality. However, in tight oil plays, kerogen can trap oil by sorption, rendering it non-producible; and highly viscous bitumen can clog pore throats, reducing both permeability and the produced oil fraction. Therefore, it is often not practical to use a reservoir quality metric that is based on the TOC alone. Recently, there have been efforts to use pyrolysis techniques such as Rock-Eval on core and/or cutting samples to measure quantities of light hydrocarbons in tight oil reservoirs (S1) and to use such measurements of S1 to characterize reservoir quality. The Oil Saturation Index (OSI) is defined as S1/TOC×100 as measured by Rock-Eval (mark of Vinci Technologies SA) pyrolysis on core or cutting samples. See, Jarvie, D. M., 2012, Shale resource systems for oil and gas: Part 2—Shale-oil resource systems, in J. A. Breyer, ed., Shale reservoirs—Giant resources for the 21st century: AAPG Memoir 97, p. 89-119”.